curl before version 7.51.0 doesn't parse the authority component of the URL correctly when the host name part ends with a '#' character, and could instead be tricked into connecting to a different host. This may have security implications if you for example use an URL parser that follows the RFC to check for allowed domains before using curl to request them.
{
"cpe": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "7.51.0"
}
],
"source": "CPE_RANGE"
}